Field of the Invention
The disclosure relates to a pixel structure, and in particular to a pixel structure with high light penetration, capable of efficiently controlling feedthrough.
Description of the Related Art
For vertical alignment (VA) wide viewing angle technology, if the efficiency of liquid crystals located at a boundary between two areas with different liquid crystal orientations is unsatisfactory, light penetration of the panels will be poor. Also, when being fabricated, opaque metal lines also cause light penetration of the panels to be poor. Generally speaking, a pixel electrode design can optimize light penetration. For instance, designers try to narrow the area with low liquid crystal efficiency. However, some optical problems come up. For example, excessive capacitive coupling effects which cause crosstalk, or an asymmetrical positive/negative half-cycle voltage which results in fabrication difficulty and decreased yield and product reliability, etc.
“Feedthrough” is a capacitive coupling effect which is produced when a transistor is turned on and then turned off. Voltage is from high to low (taking CMI Corp. for example), therefore, the coupling direction is to pull the pixel electrode voltage downward. Liquid crystals will be driven in a positive/negative half-cycle AC status in order to prevent the liquid crystals from polarization which loses the original characteristics thereof. At this time, if the “feedthrough” is excessively heavy, the symmetry of positive/negative half-cycle will be decreased, resulting in fabrication and optical problems.